The present invention relates to a device for controlled inhalational administration of controlled-dosage medicated aerosols into the lungs.
The application of medicaments in the form of aerosols by inhalation into the human lungs is gaining an ever-increasing importance. It entails the problem that a rapid inhalation promotes the deposition of particles on the larynx and in the mouth and prevents the aerosol particles from penetrating into the lungs. What is moreover inexpedient is the fact that the aerosol to be applied is not quantified because it is specifically the inhalation, which should be controlled whenever possible and should be slow in particular, which promotes the deposition of the aerosol particles in the lungs. When the patient is able to breathe at any respiration rate desired the disadvantageous situation arises that the deposition of the particles in the lungs always presents a wide range of variation. With uncontrolled inhalation using supply reservoirs so far known (spacers) the patient varies both the flow (i.e. the respiration rate) and the volume of each breath.
The present invention is therefore based on the problem of improving a device of the general type outlined by way of introduction in a way such that with a simple manipulation an unproblematic controlled inhalation will be possible.
In accordance with the present invention this problem is solved by a device for controlled inhalational administration of controlled-dosage drugs into the lungs, comprising a closed recipient adapted to be charged with a predeterminable aerosol volume and from which the aerosol may be withdrawn by means of a control means for controlling the inhalant flow. Preferred features improving the invention in an expedient form are evident from the dependent patent claims.
The inventive provisions allow for a limitation of the respiratory flow in an expedient manner, which permits the adjustment of a maximum inhalant flow inhaled by the patient, with the deposition of aerosol particles in the lungs being increased. Due to different limitations of flow (e.g. by means of a critical nozzle, adjustable nozzle) it is possible to set the flow at different rates so that it will also be possible to achieve an adaptation to the administered drugs and to the patient""s capabilities.
For a limitation of the volume which can be inhaled a recipient is provided, preferably in the form of a balloon or bag, with a quantifiable aerosol amount being adjustable by the predetermined initial charge in the recipient.
It is moreover expedient that the patient""s co-ordination is limited by the inventive device in so far as initially a certain charge is defined and then discharged calmly. Moreover, due to a preferably transparent structure of the recipient or balloon, respectively, the patient can also visually check in an expedient way whether he has actually withdrawn the defined volume, and he is moreover able to follow up individual inspirations by shrinkage of the balloon.
Different volumes can be pre-selected for individual fields of application in an expedient manner, e.g. 50 to 150 ml for the preferred deposition in the conductive respiratory tract of the lungs, or 500 to 5000 ml for a preferred maximum deposition of the aerosol in the alveolar region of the lungs.
The structure of the device is extraordinarily simple to check and is presented to the patient in a form which does not disconcert him with a complex electronic system, thus promoting the general acceptance in a self-explaining form (visible discharge of a balloon).
In the inventive device the recipient, which is configured as a bag or balloon, is charged with a defined aerosol quantity which is predetermined by the size of the recipient. The aerosol can be produced in a conventional manner by metered-dosage aerosols, dry powder inhalators, ultrasonic or atomiser systems. In correspondence with a preferred embodiment of the invention, a balloon is disposed in a transparent recipient, e.g. of Plexiglas, which permits a comfortable operation by the patient due to its shape, e.g. with a handling element in the form of a recessed grip.
The patient then inhales the contents of the bag, with an adjustable valve or a critical nozzle, respectively, which forces him to discharge the bag slowly. This inhalation flow can be varied by adjustment of a critical nozzle or an adjustable valve whilst the patient can directly visually check the amount of the inhaled aerosols insofar as after inspiration of a quantified predetermined amount of the aerosol the bag is empty.
Depending on the application, various volumetric sizes are envisaged for the housing. If, for instance, the aerosol should be deposited exclusively or preferably in the conductive respiratory tract small housings with volumes in the range from 50 to 250 ml are advisable whereas when the deposition is demanded mainly or exclusively in the alveolar region housings with volumes between 600 and 5000 ml may be provided. Here the rule applies that the aerosol arrives in the alveolar region the more efficiently and in a higher quantity, the deeper inhalation is.
In correspondence with the claimed features it is hence expedient to dispose the recipient in a housing which may be transparent, at least partly, for a check of the charging level in the recipient, with the recipient being connected to an inhalation mouthpiece and with the housing being provided with a charging valve. The means for adjusting the inhalant flow is designed to include an adjusting valve or a so-called critical nozzle.
The recipient has, at least partly, an elastic configuration, preferably it resumes elastically its initial shaped and preferably it is designed in the form of a bag or balloon whilst the housing is provided with a handling element which is preferably integrated into the shape of a handle. This handling element may preferably be designed as recessed grip whilst the charging valve is expediently disposed in the region of this handling element.